跨媒体互动对印刷业有利？有弊？

在上期的报告中,我们谈到用户越来越多地集中资源．将文件应用程序和跨媒体互动（CMI）组合在一起。在本期的评论中,我们要探讨企业对跨媒体互动如此感兴趣的原因．跨媒体互动的兴起,以及跨媒体互动正在对印刷行业产生的积极影响。     

Tracer studies on an aerated lagoon

The city of Palmerston North, New Zealand, has two aerated lagoons as its secondary treatment facility. Interest about treatment efficiency led to an investigation into the hydraulics in the second lagoon to determine if further optimisation was viable. A tracer study using rhodamine WT was undertaken to ascertain the stimulus response output. Samples were also taken at 24 points within the lagoon to determine the tracer concentration profile throughout the lagoon. The mean residence time was determined to be 39.9 h compared with a theoretical residence time of 55.4 h. Peak concentration of the tracer at the outlet occurred at 0.44 of the mean residence time. The results of the tracer study pointed to 28% of volume being dead space. A subsequent sludge survey indicated that 26% of the design volume of the lagoon was filled with sludge. While the curved geometry of the lagoon did not appear to impact the hydraulics the fact that the first aerator is confined in a relatively smaller area will have locally boosted the mixing energy input in this inlet zone. From interpretation of the tracer response and the tracer distribution profiles it appears that the aerators are mixing the influent into the bulk flow effectively in the front end of the lagoon and that there was no evidence of any substantive short-circuiting path of concentrated tracer around to the outlet. The tracer distribution profiles gave direct insight as to how the tracer was being transported within the pond and should be used more often when conducting tracer studies. Comparison with the literature indicated that the lagoon's hydraulic efficiency was on par with a baffled pond system and it would be expected that addition of several baffles to the lagoon would provide minimal further improvement.     

Construction defect management using a telematic digital workbench

Real-time, rich-media data communication between the construction site and the off-site design office is becoming one of the important research areas in information technology for construction. This paper presents the concept of a telematic digital workbench, a horizontal tabletop user interface integrating mobile computing and wireless communication to facilitate synchronous construction site to office collaboration. We demonstrate the capabilities and potentials of this system concept for construction defect management. The on-site crew uses a handheld mobile device to collect defect information and transfers the information to the design office through wireless communication by sending the information to a database listener. The digital workbench application monitors the database and synchronizes the location of the visual information on the site with the 3D model on the server. Integrated with 3D viewing capability in a CAD system, designers can interact with the combined model/site data using a horizontal and vertical screen. A case study compared the telematic digital workbench against paper-based and Pocket PC-based methods for defect management in a controlled laboratory experiment. The case study results show that the telematic digital workbench has the potential to improve the accuracy of matching site data to digital data and reduce information loss between site and office collaboration.     

Dust in the Earth system: the biogeochemical linking of land,air and sea

Understanding the response of the Earth's climate system to anthropogenic perturbation has been a pressing priority for society since the late 1980s. However, recent years have seen a major paradigm shift in how such an understanding can be reached. Climate change demands analysis within an integrated 'Earth-system' framework, taken to encompass the suite of interacting physical, chemical, biological and human processes that, in transporting and transforming materials and energy, jointly determine the conditions for life on the whole planet. This is a highly complex system, characterized by multiple nonlinear responses and thresholds, with linkages often between apparently disparate components. The interconnected nature of the Earth system is wonderfully illustrated by the diverse roles played by atmospheric transport of mineral 'dust', particularly in its capacity as a key pathway for the delivery of nutrients essential to plant growth, not only on land, but perhaps more importantly, in the ocean. Dust therefore biogeochemically links land, air and sea. This paper reviews the biogeochemical role of mineral dust in the Earth system and its interaction with climate, and, in particular, the potential importance of both past and possible future changes in aeolian delivery of the micro-nutrient iron to the ocean. For instance, if, in the future, there was to be a widespread stabilization of soils for the purpose of carbon sequestration on land, a reduction in aeolian iron supply to the open ocean would occur. The resultant weakening of the oceanic carbon sink could potentially offset much of the carbon sequestered on land. In contrast, during glacial times, enhanced dust supply to the ocean could have 'fertilized' the biota and driven atmospheric CO(2) lower. Dust might even play an active role in driving climatic change; since changes in dust supply may affect climate, and changes in climate, in turn, influence dust, a 'feedback loop' is formed. Possible feedback mechanisms are identified, recognition of whose operation could be crucial to our understanding of major climatic transitions over the past few million years.     

Biomimetic Representation with Enzyme Genetic Programming

Erratum

Biomimetic Representation with Enzyme Genetic Programming     

A statistical approach to model simplification and multiobjective analysis

Evolving national energy supply/demand distribution systems rely, at least in part, on quantifiable factors such as local and national environmental restrictions, resource availability (type, price, and quantity) and the associated transportation infrastructure, the amount and price of capital available to consumers and suppliers of energy, total annualized system cost, including the annualized cost of end-use devices, and the demands for energy and their price/supply responsiveness. The evolution also depends on nonquantifiable factors such as personal, regionally aggregated, or even national “utility functions” and institutional or social barriers. Many models have been formulated which attempt to simulate these complex interactions.This paper describes a systematic statistical methodology for capturing, both visually and quantitatively, the trade-offs between competing quantifiable, differentiable objective functions in a model of the national energy system (Brookhaven Energy System Optimization Model). The aim is to provide decision makers with a more easily understood tool and a more easily defensible methodology on which trade-offs between certain sensitive and competing energy issues can be based. The methodology has the additional advantage of providing insights into the inherent structural relationships of the model (model simplification).